Prosthetic conduits have worse outcomes compared with great saphenous vein conduits in femoropopliteal and infrapopliteal bypass in patients with chronic limb-threatening ischemia

Objective: Single segment great saphenous vein (SSGSV) traditionally has been considered the gold standard conduit for infrainguinal bypass. There are data supporting similar outcomes with prosthetic femoral-popliteal bypass. Moreover, some investigators have advocated for prosthetic conduit for femoral tibial bypass when GSV is inadequate or unavailable. We sought to evaluate long-term outcomes of infrainguinal bypass based on conduit type for treating chronic limb-threatening ischemia (CLTI).

Methods: Data from the Best Endovascular vs Best Surgical Therapy of Patients with CLTI multicenter, prospective, randomized controlled trial, comparing infrainguinal bypass with endovascular therapy in patients with CLTI, were evaluated. In this as-treated analysis, we compared outcomes of infrainguinal bypass using prosthetic, alternative autogenous vein (AAV), and cryopreserved vein (Cryo) with SSGSV bypass. Kaplan-Meier and multivariable analyses were performed to examine the associations of conduit type with major adverse limb events (MALE), reinterventions, above-ankle amputations, and all-cause death rates.

Results: In total, 784 bypasses were analyzed (120 prosthetic, 33 AAV, 21 Cryo, AND 610 SSGSV). For prosthetic and SSGSV, the distribution was 357 femoropopliteal (93 prosthetic and 264 GSV) and 373 infrapopliteal (27 prosthetic and 346 GSV). The mean age for the overall cohort was 67.1 years; 27.4% were female, 29.9% were non-White, and 11.5% were of Hispanic ethnicity. Patients undergoing prosthetic bypass were older (69.2 years vs 66.7 years); more likely to have chronic obstructive pulmonary disease (22.5% vs 14.0%), prior coronary artery bypass grafting (88.9% vs 66.5%), and prior stroke (23.3% vs 14%); but less often were of Hispanic ethnicity (5.8% vs 12.6%) and had diabetes (59.2% vs 71.3%) (P < .05 for all). For femoropopliteal bypass, use of prosthetic conduit was associated with increased major reinterventions at 3 years overall (19.0% vs 11.5%; P = .06) and on risk-adjusted analysis (hazard ratio [HR], 2.13; 95% confidence interval [CI], 1.09-4.2; P = .028). No significant differences in MALE or death, above-ankle amputation, or death were observed. Outcomes were similar for bypasses to above-knee popliteal targets and below-knee popliteal targets. For infrapopliteal bypass, the use of a prosthetic conduit was associated with increased major reintervention (25.3% vs 10.3%; P = .005), death (68.6% vs 34.8%; P < .001), and MALE or death (90.0% vs 48.1%; P < .001) at 3 years. After risk adjustment, infrapopliteal bypass with prosthetic conduit was associated with higher major reintervention (HR, 4.14; 95% CI, 1.36-12.6; P = .012), above-ankle amputation (HR, 4.64; 95% CI, 1.59-13.5; P = .005), death (HR, 2.96; 95% CI, 1.4-6.2; P = .004), and MALE or death (HR, 3.59; 95% CI, 1.64-7.86; P = .001) compared with bypass with SSGSV. Overall, AAV had similar outcomes at 3 years as SSGSV; however, Cryo had significantly higher above-ankle amputation (50.0% vs 12.8%) (HR, 4.2; 95% CI, 1.68-10.5; P = .002), major reintervention (41.9% vs 10.7%) (HR, 3.12; 95% CI, 1.18-8.22; P = .02), and MALE/death (88.8% vs 37.8%) (HR, 2.96; 95% CI, 1.43-6.14; P = .004).

Conclusions: The use of a prosthetic conduit in infrainguinal bypass is associated with inferior outcomes compared with bypass using SSGSV, particularly for bypass to infrapopliteal targets. Cryo grafts were infrequent and also demonstrated inferior outcomes. SSGSV remains the preferred conduit of choice for infrainguinal bypass.